liquefaction pathways of bituminous subbituminous coals andtheir

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I Coal fig. N0.8 @)(IS min.) Initial coal CB treated coal Benlinck (15 min.) Initial coal CB treated coal PI. of Ayr, 15 min. Initial coal CB treated coal -one week -3 hours Pt. of Ayr, 60 min. Initial coal CB-treated coal Table 1 Tetralin Extraction Results DCM-solubles* Pyr soIslDCM- Pyr. insols insols 43.9 , 52.4 3.7 62.8 31.0 6.2 31.5 49.9 18.6 28.9 46.9 24.4 59.9 25.2 14.9 56.6 28.9 14.5 18.0 52.9 29.1 20.1 48.8 31.1 28.9 27.9 43.2 33.6 25.1 41.3 29.2 22.3 48.5 37.3 36.2 26.5 46.7 29.7 23.6 * = 100 - %DCM-insols, includes DCM soluble liquid product + gas +water. (a) = mean of duplicate runs from ref. 11. Solventkoal(15 min. extlaction time) HAO, Pt of Ayr Initial coal CB-treated coal Naphthalene, Pt. of AyA@ Initial coal CB-treated coal Naphthalene, Bentinck (8) Initial coal CB-treated coal (a) = mean of duplicate runs %&Coal CCM-solubles* Pyr sols/DCMinsols Pyr. insols 18.5 31.1 50.4 29.9 30.2 39.9 13.6 15.9 70.5 21.0 19.2 57.8 21.7 24.8 53.5 22.1 20.6 57.3 570
THE STRUCTURAL &=RATION OF HUMINlTE BY LOW SEVERITY LIQUEFACTION Kurt A. Wenzel, Pahick G. Hatcher, George D. Cody, and Chunshan Song Fuel Science Program The Pennsylvania State University University Park, Pa 16802 Keywords: low seventy liquefaction, coal suucture, huminite Hydrous pyrolysis experiments were preformed on low-rank coalified wood to investigate the chemical transformations that occur in huminite (vimnite) during low seventy liquefaction. The coal chosen for the experiments was of lignite rank. It consists of a single maceral huminite which consists predominantly of guaiacol- and catechol-like suuctrns. These structures are believed to be responsible for many of the retrogressive reactions during liquefaction (1). Tubing bomb reactions were varied with reaction times ranging from 30 minutes to 240 hours and temperatures ranging from 100°C to 350OC. Suuctural characterization of the reacted residues were quantified by solid state 13C NMR and flash pyrolysis/gas chromatography/mass spectrometry. The combined analytical techniques show there is a progressive loss of oxygen which corresponds with the loss of catechols and guaiacols with increasing thermal stress. Further, dehydration of these catechol structures involves the transformation to phenol, and alkyl phenol structures that make up the macromolecular structure of the altered coalified wood. Dealkylation is also a dominant reaction pathway, as revealed by a decrease in alkyl substitutents in the residue. Detailed studies using NMR specuoscopic and pyrolysis GCMS techniques indicate that the natural evolution of humic coals proceeds through several fundamental stages (2-6). The transformation of huminite to viuinite is characterized by reactions which result in complete demethylation of methoxy phenols to catechols and a concomitant reduction in catechols (and alkylated catechols), presumably through reaction, to form phenols and cresols; the details of the catechol reaction are so far unknown. Low severity hydrous pyrolysis of lignite parallels many of the natural coalifcation reactions. Recently, Siskin et al. (7) have demonstrated that many of the reactions which typify coalification are. facilitated, if not initiated, in the presence of water. They recognized that since coalification occurs in a water saturated system, water may play an integral role in the geochemistry of coalification. From their study of an enormous number of reactions with model compounds, several mechanisms with direct bearing on the chemical structural evolution of coal during liquefaction under hydrous conditions are. clear. The demethylation reaction, for example, has been shown to be acid catalyzed yielding phenol as the predominant product (8). The mechanism by which the alkyl-aryl ether linkage (beta-0-4) of the modified lignin is rearranged to the beta-C-5 linkage may reasonably be expected to parallel the mechanism that Siskin et al.(7) demonstrated for their model compound study of the aquathermolysis of benzyl phenyl ether in which they observed significant yield of 2 benzyl phenol; this product is a perfect analog for the rearrangement necessary to yield the beta-C-5 linkage. 571
Page 1 and 2:
LIQUEFACTION PATHWAYS OF BITUMINOUS
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the conversion of A+P and O+G with
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Asphaltcncs PrCasphaltenCS Cwr%, da
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NEW DIRECTIONS TO PRECONVERSION PRO
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ecause of incorporation of the coal
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should be considered more. The step
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17 18 Run no. 0 cys I ToS-CyS TS-To
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INTRODUCTION Effects of Thermal and
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apid decline in modulus. The loss m
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-0.01- . 04 5 -0.03- E 6 -0.0s- c)
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Assessment of Small Particle Iron O
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yields are calculated by subtractin
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conversion is greater than the corr
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Table 3. Effect of Superfine Iron O
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EFFECT OF A CATALYST ON THE DISSOLU
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inherent volatility of Mo(CO), perm
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Analysis of the quantity and compos
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$ EO .- 0 m L 0 c 0 0 > 40 300 350
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0 0 0 0 0.000 0.005 0.010 0.015 0.0
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of these studies indicate that cont
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Different levels of adsorption occu
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Nominal 2 Table 1. Concentration of
Page 45 and 46: - iF m 1.6 1.4 1.2 - - - 1- 0 0.8 -
Page 47 and 48: RESULTS AND DISCUSSION Swelling of
Page 49 and 50: . . % . . 9 'HF 0 0 0 *. . 0 . . 0
Page 51 and 52: 1.50 KQ 1.00 0.50 I / ' 02 525 I 1
Page 53 and 54: hydrogen atoms. The hydrogen atoms
Page 55 and 56: D to generate more D atoms. It is r
Page 57 and 58: 12. a. Poutsma, M. L.; Dyer, C. W.
Page 59 and 60: Figure 3. Minimum Steps to Explin D
Page 61 and 62: Apoaratus and Procedure Microflow R
Page 63 and 64: Model ComDound Test Figure 5 shows
Page 65 and 66: Figure 1. High resolution gas chrom
Page 67 and 68: Figure 5. Product distribution for
Page 69 and 70: THQ at somewhat higher temperatures
Page 71 and 72: areas of the particles and the SEM
Page 73 and 74: Experimental Catalyst Precursors an
Page 75 and 76: impregnating solvent. Table 3 shows
Page 77 and 78: of MoCo-TC2 at the level of 0.5 wt%
Page 79 and 80: Table 4. Effect of Temperature Prog
Page 81 and 82: In the past, chemical treatments in
Page 83 and 84: The effect of Corn20 preaatment on
Page 85 and 86: Reaction Time Figure 1 - Schematic
Page 87 and 88: DISSOLUTION OF THE ARGONNE PREMIUM
Page 89 and 90: A much more def~tive trend is seen
Page 91 and 92: EFFECT OF CHLOROBENZENE TREATMENT O
Page 93 and 94: same conditions and an extraction t
Page 95: ACKNOWLEDGEMENT The authors thank t
Page 99 and 100: to be originally derived from demet
Page 101 and 102: 145 30 I --/---Jh I , , I I , 250 2
Page 103 and 104: THE EFFECTS OF MOISTURE AND CATIONS
Page 105 and 106: 1 for the Zap lignite. These result
Page 107 and 108: content of the samples ion-exchange
Page 109 and 110: Table 1. F'yrolysis Results of Vacu
Page 111 and 112: 585 I
Page 113 and 114: EFFECT OF TEMPERATURE, SAMPLE SI2E
Page 115 and 116: of some of the thermobalance runs.
Page 117 and 118: 2. The mechanism of drying is a uni
Page 119 and 120: Influence of Drying and Oxidation 0
Page 121 and 122: "c gives W conversion mpared to the
Page 123 and 124: Table 1. Products dismbutions (dmmf
Page 125 and 126: - 50 45 40 E 35 2 30 E T) 25 ap 20
Page 127 and 128: Influence of Drying and Oxidation o
Page 129 and 130: FTIR . . of the L m To investigate
Page 131 and 132: CONCLUSIONS The characexizntion of
Page 133 and 134: A b S 0 r b a n C e A b s 0 r b a n
Page 135 and 136: An NMR Investigation of the Effd of
Page 137 and 138: for determining the area of the pea
Page 139 and 140: of the ronl roniponcnte nnd (2) the
Page 141 and 142: 2w 180 160 9 140 120 P loo f 80 P O
Page 143 and 144: 25 I 20 ' + 0 Drying lime, hours Fi
Page 145 and 146: substructure have been identified a
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Pyridine extraction showed that 60
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Figure 1. Reflected white-light pho
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Table 3. Pyridine Extraction Sample
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A bang-bang control strategy was us
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increased from 120°C to 135”C, r
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* wt% based on the amount of naphth
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Use of Biocatalysts for the Solubil
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Results Enzyme Modification with Di
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Conclusions Reducing enzymes can be
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Dynamics of the Extract Molecular-W
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where yi = (x-xi !/pi. The zero mom
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satisfactory agreement between theo
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0.8 0.6 0.4 0.2 “E \ bo Y, - 1 0
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The Use of Solid State C-13 NMR Spe
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differences lie in the fact that th
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I- z W 0 K W n PROTONATED AROMATIC
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ZAP WIO SIDE CHAINS IN PYRIDINE EXT
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ORGAFlIC VOLATILE MATER AND ITS SUL
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(Figure 1). They indicated that the
Page 185 and 186:
Table 3. Elemental analysis of arom
Page 187:
1- 700'C Figure 3. GClFID chromatog
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